JPH0159860B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION (Industrial Field of Application) The present invention relates to a method for producing concentrated soybean protein from defatted soybeans for use in the production of meat-like foods.

(Prior Art) The prior art will be explained based on the process diagram shown in FIG. In order to produce textured (fibrous) concentrated soy protein, NSI is produced by removing fats and oils from soybeans by solvent extraction with a solvent such as n-hexane, and then subjecting them to low-temperature treatment.
(Nitrogen solubility index) 85 or higher undenatured defatted soybean 7 is often used as a raw material.

The above-mentioned undenatured defatted soybean 7 is subjected to an extraction step 8 in which soluble non-protein substances such as sugar and soybean unpleasant odor substances are extracted with an acid solution near the isoelectric point of protein (PH4-5) or a water-soluble organic solvent such as ethanol. Thereafter, concentrated soybean protein solid content is recovered in a solid-liquid separation step 9.

After the recovered solid content is dried in a drying step 10, it is pressurized, heated, and kneaded using an extruder 11 or the like to produce a textured concentrated soybean protein 12.
In addition, modified defatted soybeans with an NSI of 10 to 40, which are processed at high temperatures after solvent extraction to remove fats and oils from soybeans, contain a large amount of non-protein substances such as sugar, and are usually used as soybean meal for feed or brewing, but are not suitable for food use. Not used.

(Problems to be Solved by the Invention) In the conventional method for producing textured soybean protein using the extruder as the final step, when the extruder is operated at its full processing capacity, it is difficult to form textures (fibers) and It is easy to get clogged and stable continuous operation is not possible, so the drawback is that the throughput must be set below the capacity. In addition, denatured defatted soybeans treated at high temperatures contain a large amount of non-protein substances such as carbohydrates and unpleasant soy odor substances, and because of their dry solid form, it is difficult to extract and remove the impurities, making them unsuitable for food use.

(Means for Solving the Problems) The present invention has been made in view of the above-mentioned conventional problems, and includes a step of texturing defatted soybeans using an extruder, and a process of treating the processed product of the step with an acid, alkaline aqueous solution or Consisting of a step of extracting sugar content with one type of water-soluble organic solvent, a step of separating the solid-liquid mixture in the step into solid-liquid to recover the solids, and a step of drying the solids from the step. The present invention provides a method for producing a textured concentrated soy protein from defatted soybeans characterized by the following.

The above process can also be applied to modified defatted soybeans with an NSI of 10 to 40, and it is best to use a twin-screw extruder as the extruder.

(Function) Defatted soybeans from which fats and oils have been removed by a well-known process are subjected to pressure, heating, and kneading treatment using an extruder, thereby denaturing proteins to near zero NSI and organizing them. The structured soy protein is extruded from an extrusion die to atmospheric pressure and foams to become a porous material. Textured defatted soybeans are soaked and mixed in acids such as hydrochloric acid, phosphoric acid, organic acids, alkaline aqueous solutions such as sodium hydroxide, potassium hydroxide, or water-soluble organic solvents such as ethyl alcohol to remove sugar content and unpleasant odors. Soluble non-protein substances such as substances are extracted and removed. The above-mentioned solid-liquid mixture is separated into an extract and a solid by a solid-liquid separator such as a wire mesh filter, and the extract is discharged to the outside of the system for treatment. The solid content is collected and dried in a drier to obtain a textured concentrated soy protein product.

(Example) The present invention will be described below based on the process diagram of an example shown in FIG. Defatted soybeans 1 that have been defatted from soybeans by a well-known solvent extraction method are supplied to an extruder treatment step 2. The defatted soybean 1 may be denatured or unmodified, or may be in the form of powder or flakes.
Further, it may be in a dry state or a wet state, but it is preferably adjusted to have a moisture content of 8 to 14 wt%. The above-mentioned extruder may be of either a single-screw type or a bi-screw type, but it is preferable to use a bi-screw type extruder that provides good organization (fiber formation) of the product protein. Processing conditions in the extruder are pressure 30-90Kg/cm ² and temperature 120
~200°C, processing time 15-60 seconds.

The defatted soybeans are hydrated, pressurized, heated, and kneaded in an extruder, and the protein is denatured until the NSI is close to zero, organized, and extruded through the extraction die into the atmosphere, whereupon the pressure is reduced to atmospheric pressure, causing it to foam and become porous. Become. Since the porous textured soybean protein contains a large amount of soluble non-protein substances such as impurities such as sugar and soybean unpleasant odor substances, the following extraction step 3 with an extractant such as an acid, alkaline aqueous solution or a water-soluble organic solvent is performed. The above impurities are extracted and removed. When using an acid or alkaline aqueous solution as the above-mentioned extract, hydrochloric acid, phosphoric acid, or an organic acid is used as an aqueous solution with a pH of 3 to 5, and the alkaline aqueous solution is sodium hydroxide, potassium hydroxide, etc. with a pH of 9 to 12. Used as an aqueous solution. The amount of acid or alkaline aqueous solution used is 15 to 80 times that of defatted soybeans (weight ratio)
And the extraction temperature is 40~60℃. When a water-soluble organic solvent is used as the extract, it is mainly used as an aqueous solution of 60 to 80 wt% ethyl alcohol, and the amount used is preferably 3 to 5 times that of defatted soybeans (weight ratio). Further, the solvent after extraction is recovered by a distillation column and a concentrator through a solid-liquid separation step 4 described later, and is reused as an extract. The mixed liquid after the extraction process is separated into solid content and extract liquid in the next solid-liquid separation step 4. For the above-mentioned solid-liquid separation, a wire mesh filter is mainly used, and if necessary, it is thoroughly washed with water. The separated extract and washing liquid are taken out of the system and treated in a wastewater treatment device, and the separated and recovered solids are sent to the next drying step 5 and dried at a temperature of 70 to 150°C. The dried solid content becomes a product as highly purified structured concentrated soybean protein 6.

(Effects) (a) Since the defatted soybeans are extruded to make them porous and then extracted, the extraction efficiency of soluble non-protein substances such as sugars is high, and highly pure structured concentrated soybean protein can be obtained. Therefore, not only undenatured defatted soybeans but also denatured soybean protein, which had previously been used only for feed and brewing, has become available for food use.

(b) In the conventional method, when the extruder was operated at full processing capacity, the organization was insufficient and the extrusion die etc. were easily clogged, but with the present invention, stable continuous operation is possible with the original processing capacity. .

(c) In the conventional method, the extruder treatment is the final step, so only narrowly limited dryers such as spray dryers and vacuum dryers can be used for the purpose of preventing decreases in NSI when producing concentrated soy protein. However, in the present invention, there is no need to consider NSI reduction during the drying process, and since it is a structured protein, solid content may adhere to the heat transfer surface during heat transfer drying. do not have. Therefore, even if a fluidized dryer is used, uniform drying can be performed without a granulation operation, and various dryers can be used.

[Brief explanation of drawings]

FIG. 1 is a process diagram showing an embodiment of the present invention, and FIG. 2 is a process diagram of a conventional method. 1: defatted soybean, 2, 3: extruder treatment process, 3, 8: extraction process, 4, 9: solid-liquid separation process,
5, 10: Drying process, 6, 12: Textured concentrated soy protein, 7: Undenatured defatted soybean.

Claims (1)

[Claims] 1. A method for producing concentrated soybean protein from defatted soybeans, which comprises the following steps: (b) A process of texturing the defatted soybeans using an extruder; (b) A process of extracting sugar content from the processed product from the above step (a) using an acid, an alkaline aqueous solution, or a water-soluble organic solvent; (c) A step of separating the solid-liquid mixture in the above step (b) into solid and liquid and recovering the solid content, and (d) a step of drying the solid content from the above step (c). 2. The method according to claim 1, wherein the defatted soybean is modified defatted soybean with an NSI of 10 to 40. 3. Claim 1, characterized in that the extruder is a biaxial extruder,
The method described in Section 2.